1. Field of the Invention
The present invention relates to a transmission control apparatus for a belt type mild hybrid vehicle and a transmission control method using the same, and more particularly, to a transmission control apparatus for a belt type mild hybrid vehicle which reduces a shift shock that can occur in shifting of the belt type mild hybrid vehicle and controls a torque of a motor generator so as to reduce a shift time, and a transmission control method using the same.
2. Discussion of Related Art
In recent years, demands for hybrid vehicles have been increasing, and accordingly, the development of technologies applied to the hybrid vehicles have been accelerating. In particular, in a case of a mild hybrid vehicle among the hybrid vehicles, an internal combustion engine is mainly used and an electric motor is used so as to assist the internal combustion engine to thereby increase efficiency of the internal combustion engine, and therefore inexpensive development costs and low price can be achieved.
In addition, among types of the mild hybrid vehicle, there is a type in which a motor generator and an engine are interworked by a belt and the motor generator compensates for a torque of a driving shaft connected to a transmission, thereby increasing efficiency of operation of the vehicle.
Meanwhile, as a transmission applied to a vehicle, a stepped transmission in which each stage is determined excluding a Continuously Variable Transmission (CVT) is generally used.
In this manner, in the stepped transmission, in order to shift the stepped transmission to a shifting stage having a different gear ratio, a power interruption or sleep interval of a driving shaft that is a driving force input stage of the transmission and a non-driving shaft that is a driving force output stage thereof may occur.
When the driving force is maintained as is in such a power interruption or sleep interval, a momentary load is disappeared, and therefore an increase in the speed may occur, and when shifting is performed and the driving shaft and the non-driving shaft are synchronized, a larger shift shock may occur.
In addition, when motoring is maintained as is in a case in which shifting is performed at an interval in which the motor generator performs the monitoring for driving force assistance in a hybrid system, there are problems such that a shift shock becomes larger, and speeds of the driving shaft and the non-driving shaft are synchronized so that a time for which shifting is completed is increased.
In addition, in a regenerative braking interval in which the motor generator is operated in the form of a generator, power input shafts of the driving shaft and the non-driving shaft are reversed, and even in a case in which momentary shafting is performed at the moment when a power generation torque for performing power generation in the same manner is generated, there are same problems such that a shift shock becomes larger by the generation torque and a time for which the shifting is completed is increased.
Therefore, there are demands for a method of solving the above-described problems.